Prior art round balers generally have a bale forming chamber defined by an apron comprising an array of side-by-side belts, transverse slats trained on chains, a plurality of rolls or a combination of these various elements, e.g., rolls and belts. Crop material, such as hay, is picked up from the ground as the baler traverses the field, fed into a fixed or variable chamber where it is accumulated and compressed to form a cylindrical package of crop material. The formed package, while in its compacted condition inside the baling chamber, is wrapped with net, plastic film, twine or the like, to produce a completed round bale that is then ejected from the baling chamber onto the ground for subsequent handling.
Wrapping systems include a means for supplying wrapping material into the bale forming chamber, wherein a formed bale is rotating. According to a know baler, the wrapping material is inserted in the area directly above the so-called ‘stripper roll’. The net or plastic film is then wrapped around the bale after which the wrapped bale is ejected from the baler. Examples of such systems are disclosed in documents EP-A-432830, EP-A-681782, EP-A-766912 and EP-A-1264533. A problem of these systems is the fact that wrapping material may become wrapped around the stripper roll. Especially in wet conditions and when using plastic film, this problem tends to be prominent.
Mechanisms exist for scraping off crops that are sticking to one of the rolls that are guiding the apron, as shown for example in EP-A-152085, but these mechanisms are not effective for removing web material wrapped around the roll, in particular when it concerns plastic film.